WESTERN WHEATGRASS
(Agropyron smithii)

Description

Not only does South Dakota have a state flower, state rock, state soil,
state tree and state flag, it has a state grass; western
wheatgrass. This species was designated the South Dakota state grass
in 1970 by an act of the state legislature. Western
wheatgrass was chosen because it is a common species that is one of
the few that can be found throughout the entire state. If
you are looking over an area in South Dakota in early summer and see
a strange blue-green patch of grass, that's probably
western wheatgrass.

Species Distribution

The name, Agropyron , comes from the Greek words "agrios" meaning wild
and "pyros" meaning wheat. Smithii refers to the
botanist, Gerald Smith, who discovered the species. The stem of this
grass is blue-green in color and grows from 12 to 35
inches (30 to 90 cm) high. The leaves, which are also blue-green, come
off the stem at a 45 degree angle. They are stiff and
flat, mostly smooth with a strongly ribbed upper surface. The upper
surface is rough to the touch. Leaves have a dark purple
collar and auricles. The seedhead is a slender spike.

Distribution

Western wheatgrass grows in a variety of soils, especially clay, and
is found in most of the United States, except the
southeast. It is a native grass whose major range is in the northern
and central Great Plains. The species is found throughout
South Dakota, and is one of our most common grasses.

Natural History

Western wheatgrass is a cool season species that starts growing in May
and June when the temperatures reach approximately
54 degrees Fahrenheit (12 degrees centigrade). The species goes dormant
in the summer, and will begin growing again in the
fall when temperatures cool. Western wheatgrass is a perennial that
reproduces both sexually, with seeds, and asexually,
with underground stems, called rhizomes . Single grass stems arise
from the spreading rhizomes.

Significance

Western wheatgrass is good forage for cattle, horses, and sheep, but
only fair quality food for pronghorn antelope and other
wildlife. This grass cures well and will therefore provide good winter
grazing or hay. It is commonly used to seed roadside
ditches and to reclaim other disturbed areas.

The vigorous rhizomes characteristic of the species make it very tolerant
of grazing pressure by domestic and wild animals.
In fact, moderate grazing stimulates production of new sprouts and
increases the vigor of the plant. Because western
wheatgrass sprouts from rhizomes , it can recover quickly from prolonged
drought. It often is the first species to fill areas
that have lost vegetation due to long dry spells.

Glossary

Asexual reproduction - the type of reproduction that is accomplished
by an individual without the help of another individual. The resulting
offspring will be genetically identical to the adult.
Auricles - ear-like lobes at the base of leaf blades.
Forage - food for animals.
Rhizome - modified underground stem that can asexually produce
a new plant.
Perennial - a plant that can live more than 2 years.

Publication of the Western Wheatgrass fact sheet was funded by
the S.D. Department of Game, Fish and Parks, Division of
Wildlife, Pierre, SD in cooperation with a Natural Resource Conservation
Education Grant from the U.S. Forest Service.